Glulam

Glulam, or glue-laminated timber, is one of the earliest engineered timber products. The German Gymnasium, constructed in 1864-65 near King's Cross station in London, is an early example where the side to side and edge to edge lamination of pieces of planed timber allowed large distances to be spanned.

Curved beams and arches can be produced with very wide spans such as those in the Richmond Olympic Oval Roof, Vancouver, the Sheffield Winter Gardens, and the Lillehammer Olympic Stadium in Norway.

Glulam beams are used throughout the UK in many buildings, ranging from supermarkets to sports halls to schools, for example.

A key factor in producing endless lengths of timber for lamination into beams was the development of finger joints which are produced with pairs of matched rotary cutters. In commercial production glulam is traditionally bonded with phenolic adhesives which contain formaldehyde and cure with water as a condensation product. One part adhesives such as polyurethanes, which are formaldehyde - and solvent-free offer a more environmentally acceptable alternative.

The major limitation in the length of a glulam member is the feasibility of transporting the timber to site, thus the more common average maximum length is 12 metres (ie a truck trailer length).